JEE Mains · Physics · STD 12 - 13. Nuclei
The activity of a radioactive sample falls from \(700 \;\mathrm{s}^{-1}\) to \(500\; \mathrm{s}^{-1}\) in \(30\;min\). Its half life is close to.........\(min\)
- A \(66\)
- B \(52\)
- C \(72\)
- D \(62\)
Answer & Solution
Correct Answer
(D) \(62\)
Step-by-step Solution
Detailed explanation
\(A=A_{0}\left(\frac{1}{2}\right) \frac{t}{T_{1 / 2}}\) \(500=700\left(\frac{1}{2}\right) \frac{t}{T_{1 / 2}}\) \(0.7 \approx\left(\frac{1}{2}\right) \frac{t}{T_{1 / 2}}\) \(\left(\frac{1}{2}\right)^{1 / 2} \approx \frac{t}{T_{1 / 2}}\)…
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